In this article, we describe the epidemiology, genetics, clinical manifestations, and management of HPS. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.The interstitial lung diseases (ILDs) are a group of progressive disorders characterized by chronic inflammation and/or fibrosis in the lung. While some ILDs can be linked to specific environmental causes (i.e., asbestosis, silicosis), in many individuals, no culprit exposure can be identified; these patients are deemed to have "idiopathic interstitial pneumonia" (IIP). Family history is now recognized as the strongest risk factor for IIP, and IIP cases that run in families comprise a syndrome termed "familial interstitial pneumonia" (FIP). Mutations in more than 10 different genes have been implicated as responsible for disease in FIP families. Diverse ILD clinical phenotypes can be seen within a family, and available evidence suggests underlying genetic risk is the primary determinant of disease outcomes. Together, these FIP studies have provided unique insights into the pathobiology of ILDs, and brought focus on the unique issues that arise in the care of patients with FIP. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.This review provides an updated approach to the diagnosis and management of hypersensitivity pneumonitis (HP). The importance of using a multidisciplinary discussion to increase diagnostic and treatment confidence is emphasized. https://www.selleckchem.com/products/nik-smi1.html The role of Bayesian reasoning is highlighted throughout, underscoring the importance of hypothesis generation (differential diagnosis) and diagnostic test interpretation based on the probability of HP. Probability estimates of diagnostic certainty (i.e., a confident versus a working diagnosis) and treatment thresholds are carefully examined.Therapeutically, beyond antigen avoidance and newly available antifibrotic therapy for patients with a progressive fibrosing phenotype; the role, timing, and expected response to anti-inflammatory therapy in individual patients are unanswered questions. Since the evidence and validation of testing generally performed during the diagnostic work-up and longitudinal monitoring of HP is feeble at best, the viewpoints discussed are not intended to resolve current controversies but rather to provide a conceptual framework for evaluating discordant information when evaluating and caring for patients with HP. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.Immunoglobulin G4-related disease (IgG4-RD) is a systemic fibroinflammatory disorder that has been recognized to involve virtually any organ in the body and typically manifests mass-like lesions (tumefactive). Although initial reports of this disease (autoimmune pancreatitis [AIP]) were described in the Japanese population, it has since been reported worldwide. It is most commonly seen in adults of middle age or older, more often men than women. The pathogenesis of IgG4-RD is largely unknown, but genetic factors, microorganisms, and autoimmunity are thought to play important roles. Serum IgG4 concentration is elevated in the majority of patients with IgG4-RD but is a nonspecific finding. Characteristic histopathologic features include dense lymphoplasmacytic infiltrate, fibrosis (often in storiform pattern), and obliterative phlebitis. Lung involvement in IgG4-RD was first reported in 2004 in two patients with AIP and coexisting interstitial lung disease. Since then, a wide spectrum of intrathoracic involvement has been reported and includes not only parenchymal lung diseases but also pleural, airway, vascular, and mediastinal lesions. Thoracic involvement in IgG4-RD is often found incidentally during the workup of extrathoracic lesions but can sometimes be the presenting abnormality. The diagnosis of IgG4-RD requires correlation of clinical, laboratory, imaging, and histopathologic features. Glucocorticoids are the first-line therapy but other options including B cell depletion are being investigated. IgG4-RD is generally associated with an indolent clinical course and most patients improve with glucocorticoid therapy. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.Nonspecific interstitial pneumonia (NSIP) is a complex disorder commonly associated with other conditions such as connective tissue diseases (CTDs) and environmental exposures. Although idiopathic NSIP has been recognized as a separate clinical entity, recent studies have suggested that a proportion of these cases have autoimmune features suggestive of underlying CTDs. The diagnosis of NSIP usually carries a better prognosis compared with idiopathic pulmonary fibrosis but has an unpredictable natural history. Its pathogenesis is thought to be an inflammatory-driven process involving multiple pathways, including a genetic predisposition. The lack of specific clinical features often makes the diagnosis of NSIP difficult. The huge variability of radiological and histological features seen in NSIP adds to the complexity of achieving an accurate diagnosis of NSIP and a multidisciplinary approach is often required. There is a lack of consensus on the optimal management strategy of NSIP. Early clarification of the goals of therapy and close monitoring for the progression of disease is important across the spectrum of NSIP irrespective of its etiology. Although immunosuppressive and immunomodulatory agents are commonly used for severe and progressive disease, the therapeutic landscape of NSIP is constantly evolving as the role of newer agents such as antifibrotic therapies is being explored. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.Combined pulmonary fibrosis and emphysema (CPFE) is a clinical entity characterized by the combination of upper lobe emphysema and lower lobe fibrosis, the latter owing to various interstitial lung diseases. These patients have a characteristic lung function profile, with relatively preserved dynamic and static lung volumes, contrasting with a significant reduction of carbon monoxide transfer. The pathogenic mechanisms leading to the coexistence of emphysema with fibrosis remain unclear and different theories have been proposed. CPFE is frequently complicated by pulmonary hypertension, acute exacerbations, and lung cancer leading to poor natural history and prognosis. The syndrome of CPFE represents a distinct pulmonary manifestation in the spectrum of lung diseases associated with connective tissue diseases. Currently, there are no established recommendations regarding the management of patients with CPFE. We provide a review on the existing knowledge of CPFE regarding the epidemiology, pathogenesis, clinical manifestations, radiologic appearance, complications, prognosis, and possible treatment options.